[223c]
partakes of no mean art, but of a very many-sided one. And we must indeed do so, for in our previous talk it presents an appearance of being, not what we now say it is, but another class.
Theaetetus
How so?
Stranger
The acquisitive art was of two sorts, the one the division of hunting, the other that of exchange.
Theaetetus
Yes, it was.
Stranger
Now shall we say that there are two sorts of exchange, the one by gift, the other by sale?
Theaetetus
So be it.
Stranger
And we shall say further that exchange by sale is divided into two parts.